Capacitance Electronic Disc facts for kids

The Capacitance Electronic Disc (also called a CED) was a special type of video disc. It was like a big, black record, but instead of just music, it stored movies and sounds! The company RCA first made it in 1964.

Unlike modern CDs or DVDs, the CED was an analog format. This means it stored information as tiny grooves, just like an old record. The disc itself was kept safe inside a plastic case. This was important because the disc was very easy to damage if you touched it. The plastic case also had a label with the movie's name and a short summary.

History of the CED

Even though the first CED was made in 1964, you couldn't buy them until 1981. When they finally came out, about 200 different movies were available on CED. Each movie cost between $15 and $35. The price depended on how long the movie was.

However, the CED didn't sell very well. One big reason was that you couldn't record your own shows or movies onto a CED disc. People preferred video tapes because you could record with them. Because of this, RCA stopped making CEDs in 1986.

How a CED Disc Worked

CEDs were round, flat discs made of special vinyl. They were about 30 centimeters (or 11.8 inches) wide. People often called them "12-inch discs" even though they were a tiny bit smaller. Each side of the disc had very long grooves. These grooves were about 19 miles long! They were also 37 times smaller than the grooves on a regular music record.

When a CED disc played, it spun very fast, about 450 times every minute. Each spin of the disc held several frames of both sound and picture information.

Reading the Disc

To play a CED, a tiny titanium needle gently touched the outer edge of the disc. A small electric current went through the middle of this needle. When the needle touched the bottom of a groove, it read the sound information. This sound was stored in tiny holes. The needle sensed how much air was between itself and these holes. Then, the player's electronics turned this information into sound.

The picture information was also in the grooves. It was read a bit like a regular music record. As the needle moved over the grooves, it would vibrate. The player then changed these vibrations into the pictures you saw on your screen.

Images for kids

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  Exposed CED disc

See also

In Spanish: CED para niños